A q that was not a number or was outside 1-100 was dropped and 85 used,
so q=500 was served and verified against a signature made for 85. It is
now a 400 naming q and the value, read with the generator's quality
check; only a q missing from the URL is 85.
The route also refuses with 400 a query string that cannot be decoded
(r.URL.Query() drops such a pair, so q=80% arrived as no q) and any
parameter given more than once, which was read from its first value only
(q=80&q=500 was served at 80).
Model: opus-5-5
Route tests: a q that is not a whole number from 1 to 100, an empty one
included, is a 400 naming q and the value; a parameter given more than
once is a 400 naming it; a query string that cannot be decoded is a 400
showing it. On next each is served, at 85 or at the first value given.
Model: opus-5-5